【摘要】 换热器、海洋立管等管阵结构在高速流体的冲刷下,由于流体弹性不稳定性的影响,会发生剧烈振动,这种振动可能对结构产生破坏,而且振幅较大时,管阵中的圆管将发生碰撞,从而使系统带有强非线性。考虑以上情况,研究了管阵中圆管的振动现象,首先建立系统的运动偏微分方程,使用伽辽金法进行离散,然后采用数值方法求解系统响应。并研究了流速和倾斜角度对系统运动的影响。研究结果表明:随着倾斜角不断增大,系统临界流速逐渐增大,相较于轴向流来说,横向流对系统临界流速的影响更大;当倾斜角为60°时,随着流速不断增加,系统发生颤振失稳,依次出现极限环振动、周期1振荡、拟周期运动。相关的实际工程计算中,应当更多地考虑具有倾斜角的来流对系统运动的影响。更多还原

【Abstract】 Heat exchangers,ocean risers and other tubular structures will vibrate violently under the erosion of highspeed fluid,due to the influence of fluid elastic instability,this vibration may cause damage to the structure. When the amplitude is large,the round tube in the array will collide,which makes the system highly nonlinear. Considering the above situation,the vibration phenomenon of the round tube in the arrays is studied. Firstly,the governing equations of system are established and the ordinary differential equations are induced by using the Galerkin’s method. then solve the system response by the numerical method. The inclined angles of the flow are changed to study the influencesof the inclined angle on the stabilities of the systems. The results show the flutter critical flow velocity increases with increasing inclined angle. When the inclined angle is 60°,the system goes through limit cycle oscillation,periodic-1 motion and quasi-periodic motion with increasing flow velocity. In the practical engineering calculation,more consideration should be given to the influence of the flow with an inclined angle on the system motion.更多还原